1211220112011 has 128 divisors (see below), whose sum is σ = 2235985274880. Its totient is φ = 564875845632.

The previous prime is 1211220111967. The next prime is 1211220112021. The reversal of 1211220112011 is 1102110221121.

It is a happy number.

It is not a de Polignac number, because 1211220112011 - 2⁷ = 1211220111883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211220112021) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 4858180 + ... + 5101406.

It is an arithmetic number, because the mean of its divisors is an integer number (17468634960).

Almost surely, 2^{1211220112011} is an apocalyptic number.

1211220112011 is a deficient number, since it is larger than the sum of its proper divisors (1024765162869).

1211220112011 is a wasteful number, since it uses less digits than its factorization.

1211220112011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243333.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1211220112011 its reverse (1102110221121), we get a palindrome (2313330333132).

It can be divided in two parts, 1211220 and 112011, that added together give a palindrome (1323231).

The spelling of 1211220112011 in words is "one trillion, two hundred eleven billion, two hundred twenty million, one hundred twelve thousand, eleven".